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Y-rich hainite occurs in nepheline syenite pegmatite of the Sakharjok massif (Kola Peninsula, Russia). It forms euhedral prismatic crystals up to 2 mm in length as well as rims around an unidentified mineral phase (silicate of Ca, Y, Zr and Ti). The mineral is triclinic, space group P-1, a 9.6054(10), b 5.6928(6), c 7.3344(7) Å, α 89.903(2), β 101.082(2), γ 100.830(2)°, V 386.32(7) Å 3 , Z=1. The calculated density is 3.39 g/cm 3. Chemical composition of Sakharjok hainite is different from the previously published data by much higher Y and Nb contents up to 0.72 and 0.20 atoms per formula unit, respectively, by the two-to five-fold depletion in the LREEs and by the strong enrichment of the HREEs. From the single-crystal X-ray diffraction data, there is a significant amount of Y in the M1 site associated with the absence of Zr in it. Nb and Zr are concentrated in the M5 site substituting Ti. Combination of single-crystal X-ray diffraction data and electron microprobe data give the empirical formula (Ca 1.04 Y 0.63 REE 0.24 Mn 0.02) ∑1.93 (Na 0.92 Ca 0.77) ∑1.69 Ca 2.00 (Na 0. 6 5 Ca 0. 1 0) ∑ 0. 7 5 (Ti 0. 6 0 Zr 0. 2 1 Nb 0. 1 5 Fe 0. 0 3) ∑ 0. 9 9 ((Si 4.00 Al 0.02) ∑4.02 O 14) (F 2.61 O 1.39) ∑4.00 .

Batievaite-(Y), Y 2 Ca 2 Ti[Si 2 O 7 ] 2 (OH) 2 (H 2 O) 4 , is a new mineral found in nepheline syenite pegmatite in the Sakharjok alkaline massif, Western Keivy, Kola Peninsula, Russia. The pegmatite mainly consists of nepheline, albite, alkali pyroxenes, amphiboles, biotite and zeolites. Batievaite-(Y) is a late-pegmatitic or hydrothermal mineral associated with meliphanite, fluorite, calcite, zircon, britholite-group minerals, leucophanite, gadolinite-subgroup minerals, titanite, smectites, pyrochlore-group minerals, zirkelite, cerianite-(Ce), rutile, behoite, ilmenite, apatitegroup minerals, mimetite, molybdenite, and nickeline. Batievaite-(Y) is pale-cream coloured with white streak and dull, greasy or pearly luster. Its Mohs hardness is 5-5.5. No cleavage or parting was observed. The measured density is 3.45(5) g/cm 3. Batievaite-(Y) is optically biaxial positive, α 1.745(5), β 1.747(5), γ 1.752(5) (λ 589 nm), 2V meas. = 60(5)°, 2V calc. = 65°. Batievaite-(Y) is triclinic, space group P-1, a 9.4024(8), b 5.5623(5), c 7.3784(6) Å, α 89.919(2), β 101.408(2), γ 96.621(2)°, V 375.65(6) Å 3 and Z = 1. The eight strongest lines of the X-ray powder diffraction pattern [d(Å)(I)(hkl)] are: 2.991(100)(11-2), 7.238(36)(00-1), 3.061(30)(300), 4.350(23)(0-1-1), 9.145(17)(100), 4.042(16)(11-1), 2.819(16)(3-10), 3.745(13)(2-10). The chemical composition determined by electron probe microa n a l y s i s (E P M A) i s (w t. %) : N b 2 O 5 2 .2 5 , Ti O 2 8.01, ZrO 2 2.72, SiO 2 29.

Nikmelnikovite, Ca12Fe2+Fe3+3Al3(SiO4)6(OH)20, is a new mineral from the Kovdor massif, Kola peninsula, Russian Federation. It is the first trigonal member of the garnet supergroup. The mineral is named in honor of Academician Nikolay Nikolaevich Melnikov (1938-2018), an outstanding Soviet and Russian mining engineer, long-time (1981-2015) director of the Mining Institute of the Kola Science Center, Russian Academy of Sciences.